The word ecumenism comes from a family of Classical Greek words: oikos, meaning a “house,” “family,” “people,” or “nation”; oikoumenē, “the whole inhabited world”; and oikoumenikos, “open to or participating in the whole world.” Like many biblical words, these were invested with Christian meaning. The oikoumenē describes the place of God’s reconciling mission (Matthew 24:14); the unity of the Roman Empire (Luke 2:1) and of the kingdoms of the earth (Luke 4:5); and the world destined to be redeemed by Christ (Hebrews 2:5). The vision of one church serving God in the world came to reflect a central teaching of the early Christian faith.

In later centuries the word ecumenical was used to denote church councils (e.g., Nicaea, Chalcedon) whose decisions represented the universal church, in contrast to other councils that enjoyed only regional or limited reception. The honorary title of ecumenical patriarch was given to the Greek Orthodox patriarch of Constantinople in the 6th century because his see was located in the capital of the oikoumenē and his leadership was accepted as primus inter pares (first among equals) in the faith and mission of the whole church. The Apostles’, the Nicene, and the Athanasian creeds are called ecumenical because they witness to the faith of all Christians. Since the 19th century the term ecumenism has denoted the movement of the renewal, unity, and mission of Christians and churches of different traditions “so that the world may believe.”

Ecumenism is a vision, a movement, a theology, and a mode of action. It represents the universality of the people of God and affects the way Christians think about their faith, the church, and the world. Ecumenism is a long process that draws Christians together, uniting their life and mission and bringing the Body of Christ and the human community closer to the fulfillment of God’s purposes. Those involved in ecumenism participate in ideas, activities, and institutions that express a spiritual reality of shared love in the church and the human community. Ecumenism is characterized by the work of officially organized ecumenical bodies, the confessing and witnessing of Christians in local places, and the spirituality and actions of those who live together in love and prophetic proclamation. Far more than a program or an organization, ecumenism is, according to the British ecumenist Oliver S. Tomkins, “something that happens to the soul of Christians.”

Any unity worthy of this vision cannot be identified with political or spiritual coercion, strategies of dominance or superiority, calls for “a return to the mother church,” or expectations of monolithic uniformity or a super-church. The weapons of faith are not those of force or intolerance; neither can divisions be overcome nor authentic unity manifested by syncretism, a least-common-denominator theology, or a casual friendliness. Ecumenism accepts the diversity of God’s people, given in creation and redemption, and strives to bring these confessional, cultural, national, and racial differences into one fully committed fellowship.

Ultimately the purpose of ecumenism is to glorify the triune God and to help the one missionary church to witness effectively and faithfully among all peoples and nations. In the second half of the 20th century Christians confessed new dimensions of this vocation, especially in relation to what divides the churches. Progress was made on historical theological issues that have divided Christians through the centuries—baptism, the Eucharist, and ministry. But equally divisive among Christians are the divisions of the human family: racism, poverty, sexism, war, injustice, and differing ideologies. These issues are part of the agenda of ecumenism and bring a particular context, dynamic spirit, and urgency to the pursuit of Christian unity as well as of justice and peace. The church’s unity becomes essential for the renewal and unity of the human family. Through its unity the church becomes a sign, the first fruits of the promised unity and peace among God’s peoples and the nations.

The biblical perspective

The unity of the church and of all creation is a dominant motif in the Bible. This witness begins in the Old Testament, or Hebrew Scriptures, not the New Testament. As attested in the Bible, God established a covenant with the Hebrew people and gathered the disparate tribes into one religious nation, Israel, taking steps to overcome the alienation between God and humans and to reconcile God’s people. The tradition of ancient Judaism, therefore, was based on the reality of the one people of God. Their unity was an expression of their monotheistic faith, the oneness of God (Yahweh). According to Genesis, God created the world as one cosmos, an ordered unity determined by one single will in which all creatures are responsive to the purposes of the Creator. Yahweh chose Israel from all the nations of the world and entered into covenant with its people. Whenever men and women sinned and alienated themselves from God and from one another, God acted to bring about their reconciliation. Israel’s mission was to preserve the faithfulness and unity of all God’s people and to prepare them for the realization of the Kingdom of God.

The vision of unity is central to the Gospel of Jesus Christ and the teachings of his Apostles. Those who confess Jesus as Lord and Saviour are brought together in a new community: the church. The New Testament writers assumed that to be “in Christ” is to belong to one fellowship (Greek: koinōnia). Jesus clearly gave the mandate when at the Last Supper he offered his high-priestly intercession, praying that the disciples and all those who believe in him “may all be one; even as thou, Father, art in me, and I in thee…so that the world may believe that thou hast sent me” (John 17:21). This unity was demonstrated in the miracle of Pentecost (Acts 2) and other actions that established the primitive church—e.g., the epoch-making Council of Jerusalem (Acts 15), which negotiated conflicts between Jewish and Gentile Christians.

The early church nevertheless had many tensions and conflicts that called for ecumenical proclamations and pleas from the Evangelists and Apostles. Tensions arose between Jewish Christian churches and Gentile Christian churches, between Paul and the enthusiasts. Peter and Paul disagreed strongly over whether Gentiles had to fulfill Jewish requirements in order to be welcome at the Lord’s Supper (Eucharist). As revealed in the New Testament, the young church clearly faced the challenge of theological aberrations: Colossians refutes Gnosticism; the Johannine Epistles warn against Docetism; 2 Peter and Revelation attack false prophets.

Diversity, however, did not create schism nor allow a break in fellowship. There were no denominations or divided communities, as were to develop later in the church’s history. Division among Christians is a denial of Christ, an unthinkable distortion of the reality of the church. Amid their diversity and conflicts the early Christians remained of “one accord,” visibly sharing the one Eucharist, accepting the ministries of the whole church, reaching out beyond their local situation in faith and witness with a sense of the universal community that held all Christians together. As Paul taught the Ephesians, God’s ultimate will and plan is “to unite all things in him [Christ], things in heaven and things on earth” (chapter 1, verse 10).

The history of ecumenism

While unity is given in Christ, two diametric forces appear in the history of the church. One is the tendency toward sectarianism and division; the other is the conviction toward catholicity and unity. Ecumenism represents the struggle between them. Some of the schisms were theological conflicts foreshadowed in the apostolic church; others were internal quarrels related to liturgical differences, power politics between different patriarchates or church centres, problems of discipline and piety, or social and cultural conflicts. Nevertheless, according to the American historian John T. McNeill, “the history of the Christian Church from the first century to the 20th might be written in terms of its struggle to realize ecumenical unity.”

Early controversies

A long and continuing trail of broken relations among Christians began in the 2nd century when the Gnostics presented a serious doctrinal error and broke fellowship. Quartodecimanism, a dispute over the date of Easter, pitted Christians from Asia Minor against those from Rome. Montanism—which taught a radical enthusiasm, the imminent Second Coming of Christ, and a severe perfection, including abstinence from marriage—split the church. The Novatians broke fellowship with Christians who offered sacrifices to pagan gods during the persecutions of the Roman emperor Decius in AD 250. In the early 4th century the Donatists, Christians in North Africa who prided themselves as the church of the martyrs, refused to share communion with those who had lapsed (i.e., who had denied the faith under threat of death during the great persecutions of Diocletian and Galerius). They remained a powerful force in Africa into the 5th century and survived into the 7th despite opposition from church and state. This schism—like many since—reflected regional, national, cultural, and economic differences between the poor, rural North African Christians and the sophisticated, urban Romans.

In each century leaders and churches sought to reconcile these divisions and to manifest the visible unity of Christ’s church. But in the 5th century a severe break in the unity of the church took place. The public issues were doctrinal consensus and heresy, yet in the midst of doctrinal controversy alienation was prompted by political, cultural, philosophical, and linguistic differences. Tensions increased as the church began to define the relationship between God the Father and God the Son and later the relation between the divine and human elements in the nature and person of Jesus Christ. The first four ecumenical councils—at Nicaea (AD 325), Constantinople (381), Ephesus (431), and Chalcedon (451)—defined the consensus to be taught and believed, articulating this faith in the Nicene Creed and the Chalcedonian Definition, which stated that Jesus is the only begotten Son of God, true man, and true God, one person in “two natures without confusion, without change, without division, without separation.” Two Some groups deviated doctrinally from the consensus developed in the councils. The Nestorians taught that there are two distinct persons in the incarnate Christ and two natures conjoined as one; . Monophysites taught that there is one single nature, primarily divine. Several churches refused to accept the doctrinal and disciplinary decisions of Ephesus and Chalcedon and formed their own communities. These churches, called pre-Chalcedonian or non-Chalcedonian churches, including the Oriental Orthodox churches, became great missionary churches and spread to Armenia, Egypt, Ethiopia, Syria, Persia, and the Malabar coast of India in isolation from other churchesAfrica and throughout Central, South, and East Asia.

The schism of 1054

The greatest schism in church history occurred between the church of Constantinople and the church of Rome. While 1054 is the symbolic date of the separation, the agonizing division was six centuries in the making and the result of several different issues. The Eastern Church church sharply disagreed when the Western Church church introduced into the Nicene Creed the doctrine that the Holy Spirit proceeds not from the Father alone—as earlier Church Fathers taught—but from the Father and the Son (Latin: Filioque). When the Roman Empire was divided into two zones, Latin-speaking Rome began to claim superiority over Greek-speaking Constantinople; disputes arose over church boundaries and control (for example, in Illyricum and Bulgaria). Rivalry developed in Slavic regions between Latin missionaries from the West and Byzantine missionaries from the East, who considered this territory to be Orthodox. Disputes over authority became even more heated in the 11th century as Rome asserted its primacy over all churches. Lesser matters related to worship and church discipline—for example, married clergy (Orthodox) versus celibacy (Roman Catholic) and rules of fasting and tonsure—strained ecclesial relations. The tensions became a schism in 1054, when the uncompromising patriarch of Constantinople, Michael Cerularius, and the uncompromising envoys of Pope Leo IX excommunicated each other. No act of separation was at this time considered final by either side. Total alienation came a century and a half later, as a result of the Crusades, when Christian knights made military campaigns to save Jerusalem and the Holy Land from the Muslims. In 1204 the Fourth Crusade was diverted to attack and capture Constantinople brutally. Thousands of Orthodox Christians were murdered; churches and icons were desecrated and undying hostility developed between East and West.

Even so, certain leaders and theologians on both sides tried to heal the breach and reunite East and West. In 1274, at the second Council of Lyon, agreement was reached between the two churches over several key issues—Orthodox acceptance of papal primacy and the acceptance of the Nicene Creed with the Filioque clause. But the agreements were only a rushed action conditioned by political intrigue. As a result, reunion on these terms was fiercely rejected by the clergy and laity in Constantinople and other Orthodox provinces. A second attempt at reunion came at the Council of Ferrara-Florence that met in Italy in 1438 and 1439. A formula of union was approved by both delegations, but later it was rejected by rank-and-file Orthodox Christians.

The Reformation

The next dramatic church division took place during the Reformation in the West in the 16th century. Like other schisms, this one does not yield to simple analysis or explanation. The Reformation was a mixture of theology, ecclesiology, politics, and nationalism, all of which led to breaks in fellowship and created institutional alienation between Christians throughout Western Christendom. In one sense it was a separation, especially a reaction against the rigid juridical structures of medieval Roman Catholicism and its claim to universal truth and jurisdiction. In another sense, however, the Reformation was an evangelical and ecumenical renewal of the church as the Body of Christ, an attempt to return to the apostolic and patristic sources in order, according to Calvin, “to recover the face of the ancient Catholic Church.” All the continental Reformers Continental reformers sought to preserve and reclaim the unity of the church.

Once the separation between the Roman Catholic and new Protestant churches was complete, people on both sides tried to restore unity. Roman Catholics such as Georg Witzel and George Cassander developed proposals for unity, which all parties rejected. Martin Bucer, celebrated promoter of church unity among the 16th-century leaders, brought Martin Luther and his colleague Philipp Melanchthon into dialogue with the Swiss Reformer reformer Huldrych Zwingli at Marburg, Germany, in 1529. In 1541 John Calvin (who never ceased to view the church in its catholicity), Bucer, and Melanchthon met with Cardinal Gasparo Contarini and other Roman Catholics at Ratisbon (now Regensburg, Germany) to reconcile their differences on justification by faith, the Lord’s Supper, and the papacy. Another attempt was made in 1559, when Melanchthon and Patriarch Joasaph II of Constantinople corresponded, with the intention of using the Augsburg Confession as the basis of dialogue between Lutheran and Orthodox Christians. On the eve of the French wars of religions (1561), Roman Catholics and Protestants conferred without success in the Colloquy of Poissy. It would seem that the ecumenical projects of theologians and princes in 16th-century Europe failed unequivocally, but they kept alive the vision and the hope.

Ecumenism in the 17th and 18th centuries

Throughout the 17th and 18th centuries storms of contention and division continued to plague the churches of Europe. During these two centuries there was an eclipse of official, church-to-church attempts at unity. Instead, ecumenical witness was made by individuals who courageously spoke and acted against all odds to propose Christian unity.

In England, John Dury, a Scots Presbyterian and (later) an Anglican minister, “a peacemaker without partiality,” traveled more extensively than any other ecumenist before the 19th century. He negotiated for church unity in his own country and in Sweden, Holland, France, Switzerland, and Germany. Richard Baxter, a Presbyterian Puritan, developed proposals for union, including his Worcestershire Association, a local ecumenical venture uniting Presbyterians, Congregationalists, and Anglicans.

Efforts were undertaken in Germany and Central central Europe as well. The German Lutheran George Calixtus called for a united church between Lutherans and Reformed based on the “simplified dogmas,” such as the Apostles’ Creed and the agreements of the church in the first five centuries. Count Nicholas von Zinzendorf applied his Moravian piety to the practical ways that unity might come to Christians of all persuasions. The philosopher Gottfried Wilhelm Leibniz worked tirelessly for union between Protestants and Roman Catholics, writing an apologia interpreting Roman Catholic doctrines for Protestants. John Amos Comenius, a Czech Brethren educator and advocate of union, produced a plan of union for Protestants based upon the adoption of a scriptural basis for all doctrine and polity and the integration of all human culture.

Orthodox Christians also participated in the search for union. Metropolitan Philaret of Moscow and the Russian Orthodox theologian Aleksey S. Khomyakov expressed enthusiasm for ecumenism. Cyrillus Lukaris, Orthodox patriarch of Alexandria and later of Constantinople, took initiatives to reconcile a divided Christendom. People throughout Europe held tenaciously to the dream of ecumenism, although no attempt at union was successful.

19th-century efforts

A worldwide movement of evangelical fervour and renewal, noted for its emphasis on personal conversion and missionary expansion, stirred new impulses for Christian unity in the 19th century. The rise of missionary societies and volunteer movements in Germany, Great Britain, The Netherlands, and the United States expressed a zeal that fed the need for church unity. Enduring the harmful results of Christian divisions in different countries, Protestant missionaries in India, Japan, China, Africa, Latin America, and the United States began to cooperate.

In 1804 the British and Foreign Bible Society, an interdenominational Protestant organization, came into existence to translate the Scriptures into the world’s vernaculars and distribute the translations throughout the world. This was followed, 40 years later, by the founding of two important Christian organizations in England: the Young Men’s Christian Association (1844) and the Young Women’s Christian Association (1855). Their international bodies, the World Alliance of YMCAs and the World YWCA, were established in 1855 and 1894, respectively. The Evangelical Alliance, possibly the most significant agent of Christian unity in the 19th century, held a unique place among the volunteer associations of the age. Founded in London in 1846 (the American section was established in 1867), the alliance sought to draw individual Christians into fellowship and cooperation in prayer for unity, Christian education, the struggle for human rights, and mission.

Also pivotal in the 19th century were advocates for the visible unity of the church. In the United States, where the most articulate 19th-century unity movements were heard, the witness to the unity and union was led by three traditions. The Lutherans Samuel Simon Schmucker and Philip Schaff pleaded for “catholic union on apostolic principles.” Among Episcopalians, the visionaries for unity included Thomas Hubbard Vail, William Augustus Muhlenberg, and William Reed Huntington, who proposed the historic “Quadrilateral” of the Scriptures, the creeds, the sacraments of baptism and the Lord’s Supper, and episcopacy as the keystone of unity. Thomas Campbell and his son, Alexander, and Barton Warren Stone, members of the church of the Disciples of Christ, taught that “the Church of Christ on earth is essentially, intentionally and constitutionally one.” Ecumenism was enflamed in the hearts of 19th-century Christians and in the next century shaped the churches as never before.

Ecumenism since the start of the 20th century

The 20th century experienced a flowering of ecumenism. Four different strands—the international Christian movement, cooperation in world mission, Life and Work, and Faith and Order—developed in the early decades and, though distinctive in their emphases, later converged to form one ecumenical movement.

The modern ecumenical era began with a worldwide movement of Christian students, who formed national movements in Great Britain, the United States, Germany, Scandinavia, and Asia. In 1895 the World Student Christian Federation, the vision of American Methodist John R. Mott, was established “to lead students to accept the Christian faith” and to pioneer in Christian unity. The World Missionary Conference at Edinburgh (1910) inaugurated another aspect of ecumenism by dramatizing the necessity of unity and international cooperation in fulfilling the world mission of the church. In 1921 the International Missionary Council (IMC) emerged, bringing together missionary agencies of the West and of the new Christian councils in Asia, Africa, and Latin America for joint consultation, planning, and theological reflection. The Life and Work movement was pledged to practical Christianity and common action by focusing the Christian conscience on international relations and social, industrial, and economic problems. Nathan Söderblom, Lutheran archbishop of Uppsala, inspired world conferences on Life and Work at Stockholm (1925) and Oxford (1937). The Faith and Order movement, which originated in the United States, confronted the doctrinal divisions and sought to overcome them. Charles H. Brent, an Episcopal missionary bishop in the Philippines, was chiefly responsible for this movement, although Peter Ainslie, of the Disciples of Christ, shared the same vision and gave significant leadership. World conferences on Faith and Order at Lausanne (Switzerland; 1925), Edinburgh (1937), Lund (Sweden; 1952), and Montreal (1963) guided the process of theological consensus building among Protestants, Orthodox, and Roman Catholics, which led to approval by the Faith and Order Commission of the World Council of Churches of the historic convergence text Baptism, Eucharist, and Ministry (1982).

The World Council of Churches (WCC) is a privileged instrument of the ecumenical movement. Constituted at Amsterdam in 1948, the conciliar body includes more than 300 churches—Protestant, Anglican, and Orthodox—which “confess the Lord Jesus Christ as God and Saviour according to the Scriptures and therefore seek to fulfill together their common calling to the glory of the one God, Father, Son, and Holy Spirit.” Its general secretaries have been among the architects of modern ecumenism: Willem Adolph Visser ’t Hooft (The Netherlands), Eugene Carson Blake (United States), Philip Potter (Dominica), Emilio Castro (Uruguay), Konrad Raiser (Germany), and Samuel Kobia (Kenya). The witness and programs of the WCC include faith and order, mission and evangelism, refugee and relief work, interfaith dialogue, justice and peace, theological education, and solidarity with women and the poor. What distinguishes the WCC constituency is the forceful involvement of Orthodox churches and churches from the developing world. Through their active presence the WCC, and the wider ecumenical movement, has become a genuinely international community.

Roman Catholic ecumenism received definitions and momentum at the Second Vatican Council (Vatican II; 1962–65), under the ministries of Popes John XXIII and Paul VI, and through the ecumenical diplomacy of Augustin Cardinal Bea, the first president of the Secretariat for Promoting Christian Unity. The church gave the ecumenical movement new hope and language in the “Decree on Ecumenism” (1964), one of the classic ecumenical teaching documents. Another result of Vatican II was the establishment of a wide variety of international theological dialogues, commonly known as bilateral conversations. These included Roman Catholic bilaterals with Lutherans (1965), Orthodox (1967), Anglicans (1967), Methodists (1967), Reformed (1970), and the Disciples of Christ (1977). Topics identified for reconciling discussions include baptism, the Eucharist, episcopacy and papacy, authority in the church, and mixed marriage.

Critical to modern ecumenism is the birth of united churches, which have reconciled formerly divided churches in a given place. In Asia and Africa the first united churches were organized in China (1927), Thailand (1934), Japan (1941), and the Philippines (1944). The most heralded examples of this ecumenism are the United Church of Canada (1925), the Church of South India (1947), and the Church of North India (1970). Statistics of other united churches are revealing. Between 1948 and 1965, 23 churches were formed. In the period from 1965 to 1970, unions involving two or more churches occurred in the West Indies (in Jamaica and Grand Cayman), Ecuador, Zambia, Zaire (now the Democratic Republic of the Congo), Pakistan, Madagascar, Papua New Guinea, the Solomon Islands, and Belgium. Strategic union conversations were undertaken in the United States by the nine-church Consultation on Church Union (1960) and by such uniting churches as the United Church of Christ (1957), the Presbyterian Church (U.S.A.) (1983), and the Evangelical Lutheran Church in America (1988).

Spiritual disciplines play a key role in ecumenism, a movement steeped in prayer for unity. During the Week of Prayer for Christian Unity, celebrated every year (January 18–25), Christians from many traditions engage in prayer, Bible study, worship, and fellowship in anticipation of the unity that Christ wills.

Christianity and world religions

The global spread of Christianity through the activity of European and American churches in the 18th, 19th, and 20th centuries has brought it into contact with all other existing religions. Meanwhile, since the beginning of the 19th century, the close connection between Christian world missions and political, economic, technical, and cultural expansion haswas, at the same time, been loosened.

After World War II , the former mission churches were transformed into independent churches in the newly autonomous Asian and African states. The concern for a responsible cooperation of the members of Christian minority churches and its non-Christian fellow citizens became the more urgent with a renaissance of the Asian higher religions in numerous Asian states.

Missionaries of Asian world religions have moved into Europe, the Americas, and Australia. Numerous Vedanta centres have been were established to introduce Hindu teachings within the framework of the Ramakrishna and Vivekananda missions. In 1965 , the Hare Krishna movement was founded in the United States, attracting followers to its version of Vaishnava Vaishnavism, one of the main branches of Hinduism. Followers of South Asian Theravada (Way of the Elders) Buddhism and the Mahayana (Greater Vehicle) Buddhism Buddhism, particularly that of Japan (mainly Zen Buddhism, an intuitive-meditative sect) began world missionary activities under the influence of a Buddhist renaissance. This influence has largely Pure Land, Nichiren [especially Soka Gakkai], and Zen) and Tibet, founded temples (some of which are called “churches”), meditation centres, community centres, and other spiritual retreats. This influence penetrated Europe and North America not so much on several fronts, whether in the form of a directly organized mission as in the form of a spontaneously received flow of religious ideas and methods of meditation through literature , and philosophy, through developments in psychology and psychotherapy, and psychotherapyor through institutions within which individuals can develop a personal practice of meditation and participate in the life of the sangha (community). As a result, Christianity in the latter part of the 20th century found itself forced to enter into a factual discussion with non-Christian religions.

There has also been a general transformation of religious consciousness in the West since the middle of the 19th century. Until about 1900, knowledge of non-Christian world religions was still the privilege of a few specialists. During the 20th century, however, a wide range of people studied translations of source materials from the non-Christian religions. The dissemination of the religious art of India and East Asia through touring exhibitions and the prominence of the Dalai Lama as a political and religious figure have created a new attitude toward the other religions in the broad public of Europe and North America. In recognition of this fact, numerous Christian institutions for the study of non-Christian religions have been were founded: e.g., in Bangalore, India; in Yangon, Myanmar (Rangoon, Burma); in Bangkok, Thailand; in Kyōto, Japan; and in Hong Kong, China.

The readiness of encounter or even cooperation of Christianity with non-Christian religions is a phenomenon of modern times. Until the 18th century, Christians showed little inclination to engage in a serious study of other religions. Even though contacts with Islam had existed since its founding, the first translation of the Qurʾan Qurʾān (the Islamic scriptures) was issued only in 1141 in Toledo by Peter the Venerable, abbot of Cluny. Four hundred years later, in 1542/43, Theodor Bibliander, a theologian and successor of the Swiss Reformer reformer Zwingli, edited the translation of the Qurʾan Qurʾān by Peter the Venerable. He was subsequently arrested, and he and his publisher could be freed only through the intervention of Luther.

Christian exposure to Asian religions also was delayed. Although the name Buddha is mentioned for the first time in Christian literature—and there only once—by Clement of Alexandria about AD 200, it did not appear again for some 1,300 years. Pali, the language of the Buddhist canon, remained unknown in the West until the early 19th century, when the modern Western study of Buddhism began.

The reasons for such reticence toward contact with foreign religions were twofold: (1) The ancient church was significantly influenced by the Jewish attitude toward contemporary pagan religions. Like Judaism, it viewed the pagan gods as “nothings” next to the true God; they were offsprings of human error that were considered to be identical with the wooden, stone, or bronze images that were made by humans. (2) Besides this, there was the tendency to identify the pagan gods as evil demonic forces engaged in combat with the true God. The conclusion of the history of salvation, according to the Christian understanding, was to be a final struggle between Christ and his church on one side and Antichrist and his minions on the other, culminating with the victory of Christ.

Conflicting Christian attitudes

The history of religion, however, continued even after Christ. During the 3rd and 4th centuries , a new world religion appeared in the form of Manichaeanism, which asserted itself as a superior form of Christianity with a new universal claim of validity. The Christian Church church never acknowledged the claims of Manichaeanism but considered the religion a Christian heresy and opposed it as such.

Christianity faced greater challenges when it encountered Islam and the religions of East Asia. When Islam was founded in the 7th century, it considered the revelations of the Prophet Muhammad to be superior to those of the Old and New Testaments. Christianity also fought Islam as a Christian heresy and saw it as the fulfillment of the eschatological prophecies of the Apocalypse concerning the coming of the “false prophet” (Revelation to John). The religious and political competition between Christianity and Islam led to the Crusades, which influenced the self-consciousness of Western Christianity in the Middle Ages and later centuries. In China and Japan, however, missionaries saw themselves forced into an argument with indigenous religions that could be carried on only with intellectual weapons. The old Logos theory prevailed in a new form founded on natural law, particularly among the Jesuit theologians who worked at the Chinese emperor’s court in Peking (now Beijing). The Jesuits also sought to adapt indigenous religious traditions to Christian rituals but were forbidden from doing so by the pope during the Chinese Rites Controversy.

Philosophical and cultural developments during the Enlightenment brought changes in the understanding of Christianity and other world religions. During the Enlightenment , the existence of the plurality of world religions was recognized by the educated in Europe, partly—as in the case of the German philosopher Gottfried Wilhelm Leibniz—in immediate connection with the theories of natural law of the Jesuit missionaries in China. Only in the philosophy of the Enlightenment was the demand of tolerance, which thus far in Christian Europe had been applied solely to the followers of another Christian denomination, extended to include the followers of different religions.

Some missionaries of the late 18th and the 19th and19th centuries, however, ignored this knowledge or consciously fought against it. Simple lay Christianity of revivalist congregations demanded that a missionary denounce all pagan “idolatry.” The spiritual and intellectual argument with non-Christian world religions simply did not exist for this simplified theology, and in this view a real encounter of Christianity with world religions did not, on the whole, occur in the 18th and 19th centuries.

Modern Contemporary views

The 20th century experienced an explosion of publicly available information concerning the wider religious life of humanity, as a result of which the older Western assumption of the manifest superiority of Christianity ceased to be plausible for many Christians. Early 20th-century thinkers such as Rudolf Otto, who saw religion throughout the world as a response to the Holy, and Ernst Troeltsch, who showed that, socioculturally, Christianity is one of a number of comparable traditions, opened up new ways of regarding the other major religions.

During the 20th century , most Christians adopted one of three main points of view. According to exclusivism, there is salvation only for Christians. This theology underlay much of the history outlined above, expressed both in the Roman Catholic dogma extra ecclesiam nulla salus (“outside the church no salvation”) and in the assumption of the 18th- and 19th-century Protestant missionary movements. The exclusivist outlook was eroded within advanced Roman Catholic thinking in the decades leading up to the Second Vatican Council and was finally abandoned in the council’s pronouncements. Pope John Paul II’s outreach to the world’s religions may be seen as the practical application of the decisions of Vatican II. Within Protestant Christianity there is no comparable central authority, but most Protestant theologians, except within the extreme Fundamentalist fundamentalist constituencies, have also moved away from the exclusivist position.

In Since the mid-20th century many Roman Catholics and Protestants have moved toward inclusivism, the inclusivism—the view that, although salvation is by definition Christian, brought about by the atoning work of Christ, it is nevertheless available in principle to all human beings, whether Christian or not. The Roman Catholic theologian Karl Rahner expressed the inclusivist view by saying that good and devout people of other faiths may, even without knowing it, be regarded as “anonymous Christians.” Others have expressed in different ways the thought that non-Christians also are included within the universal scope of Christ’s salvific work and their religions fulfilled in Christianity.

The third position, which appealed to a number of individual theologians, was pluralism. According to this view, the great world faiths, including Christianity, are valid spheres of a salvation that takes characteristically different forms within each—though consisting in each case in the transformation of human existence from self-centredness to a new orientation toward the Divine Reality. The other religions are not secondary contexts of Christian redemption but independent paths of salvation. The pluralist position is controversial in Christian theology, because it affects the ways in which the doctrines of the person of Christ, atonement, and the Trinity are formulated.

Christians engage in dialogue with the other major religions through the World Council of Churches’ organization on Dialogue with People of Living Faiths and Ideologies and through the Vatican’s Secretariat for Non-Christians, as well as through a variety of extra-ecclesiastical associations, such as the World Congress of Faiths. There is a National Council of Churches of Christ in the United States, and practically every state has its own similar state-level organization. A multitude of interreligious encounters have taken place throughout the world, many initiated by Christian and others by non-Christian individuals and groups.